Surging/ jumping idle.....

[Diesel0889]

Hey guys
My idle surges some times when I come to a stop just bounces up and down for a few seconds before settling down. Just 200ish rpm up from idle. I have in stalled i.e. Pcv solution so the pcv is not my problem. Also I notice a slight stutter at idle every now and again also.( unless my 3" down pipe just makes it sound that way). Mods are as follows,


Ecs boost gauge
Apr stage 1
I.e. Pcv solution
Ecs snub mount
Ecs ra4 clutch w/ flywheel
Ecs turbo inlet pipe
Ecs oil filter housing
Beluga racing Test pipe
Oem new style piston dv
Custom 3" resonated down pipe to split 2.5" magnaflow magnapacks( changing for something more mellow) like a German car should sound.
I know I'm forgetting quite a few things also but these are the basics.... Wtf is my car doing this shit for lol. Red top Coils and plugs from ecs will be ordered tomorrow in the am so if that has any to do with it I'll find out Friday night installing them. Should I go with colder plugs from ecs or the Oem ones? Worried about winter misfires. Any help or pointers I would appreciate..... And a couple random questions about stage 2+ and rebuilding my Hpfp with jhm internals as it looks very easy as long as kept clean.... If anyone is feeling helpful or runs 2+ in there b7 a4... Thanks in advance..

[miA4]

Hey guys
My idle surges some times when I come to a stop just bounces up and down for a few seconds before settling down. Just 200ish rpm up from idle. I have in stalled i.e. Pcv solution so the pcv is not my problem. Also I notice a slight stutter at idle every now and again also.( unless my 3" down pipe just makes it sound that way). Mods are as follows,


Ecs boost gauge
Apr stage 1
I.e. Pcv solution
Ecs snub mount
Ecs ra4 clutch w/ flywheel
Ecs turbo inlet pipe
Ecs oil filter housing
Beluga racing Test pipe
Oem new style piston dv
Custom 3" resonated down pipe to split 2.5" magnaflow magnapacks( changing for something more mellow) like a German car should sound.
I know I'm forgetting quite a few things also but these are the basics.... Wtf is my car doing this shit for lol. Red top Coils and plugs from ecs will be ordered tomorrow in the am so if that has any to do with it I'll find out Friday night installing them. Should I go with colder plugs from ecs or the Oem ones? Worried about winter misfires. Any help or pointers I would appreciate..... And a couple random questions about stage 2+ and rebuilding my Hpfp with jhm internals as it looks very easy as long as kept clean.... If anyone is feeling helpful or runs 2+ in there b7 a4... Thanks in advance..

I get this too. No code or any issues with the car running, just a slight stutter sitting at a light... My technician stated that it may be oil coming through the intake and causing the very slight stutter. I don't know how true that is, but I don't lose that much oil between oil changes... maybe a quart after 4000 miles. It also may be the valve cover he stated as well. we have to wait and see until it gets worse.

[aluthman]

I'm currently troubleshooting a surging idle also. I think it's probably a vacuum leak of some sort. I don't really notice a change in idle rpm, but I can watch manifold vacuum surge on my boost gauge. I'll update this with the cause when I find it.

[Diesel0889]

Is it possible that my coil packs are causing the surging and bounce I haven't been able to find a vacuum leak anywhere and my car runs good otherwise and holds 18-20 pounds until the ko3 starts to fall on its face and we all know that's normal... I'm stumped I'm by no means a master Audi tech but I'm not a idiot. By the way my car is a 2005.5 b7 if that matters as I'm aware there are a few small changes over the years to the b7 motors that I have read of on here... Thanks in advance.

[aluthman]

A new N80 seems to have fixed mine so far. My previous N80 only lasted about 3 years and 60k miles. Not a huge deal for a part that is <$20, but I thought it would last longer.

[Der Konig]

^+1 on n80

N80 fixed a similar issue for me, just replace it for about 20 bucks. Will give you peace of mind too and is super easy to replace.

[IC Asmodai]

Indeed an new N80 fixed a similar issue with mine as well. However mine was also not wanting to start after a fuel fill up so I kinda knew it was either the N80 or Charcoal filter. How does your car act after a fill up?


Sent from The Lands of Always Winter

[aluthman]

My car acts the same after fill up as it does every other time I start it, so no issues with my charcoal filter.

[kloeb2]

I had a similar issue. RPM's hanging at idle and generally rough at lower RPM's. I figured it was something to do with the current maestro tune i have. Turns out that wasn't the cause. Pulled second gear to redline then let off the throttle yesterday and the car went into limp mode right away. It was freaking out.... redlining by itself and not responsive to throttle input.

I pulled the ic pipe to the throttle body to check it out. Turns out half of the throttle body flap was gone. Pulled the manifold to find it stuck right before the first cylinder intake valves

Just something to take a look at if you are running meth past it.